Alzheimer's Disease Pathology
Alzheimer`s disease is a degenerative disorder. People suffering from Alzheimer are reported to have memory loss and declining of thinking skills. This disease leads to behaviour changes such as confusion, disorientation, irritability creating a dependable relationship between patient and family members. Until today scientists still haven't managed to find a cure for the Alzheimer`s disorder. Yet, they try to understand and to explain the pathology of this disease.
Scientists have elaborated many theories regarding the causes which lead to Alzheimer`s disease. Many believe that factors such as environment and genetic structure have a great contribution over the human brain, leading to changes which represent the base of the disorder. It is said that people who were not engaged in activities that require mental effort are more likely to have the disease than others. Such a theory develops the idea of exercising the brain especially at old ages in order to avoid the disease. On the other hand a family history of dementia may contribute to having the disorder.
The Alzheimer affected brain is different from the normal one. The general cortex it's atrophied. Thus if the outer surface of the brain which is responsible for the intellectual functioning gets affected, the normal activities of a patient get damaged too. The autopsy reveals tow factors: in affected brains, the amount of the substance which is present in the folds is decreased. On the other hand the space between the folds gets larger. The proteins which are believed to cause neurons damage called amyloid plaques are part of a larger protein called amyloid precursor protein. The breakdown of the amyloid precursor protein leads to changes determining Alzheimer's.
Another theory explains the role of the tau proteins over the human brain. Neurofibrillary tangles also known as tau proteins represent the second cause of the Alzheimer's disease, as they have a very important role in the structure of a neuron. In patients with Alzheimer's this protein has overactive enzymes which is abnormal. Neurofibrillary causes death of the cells.
In order to determine the presence of the Alzheimer's disorder, specialists must take several tests to eliminate other possibilities that might be similar with the normal brain functions. Unfortunately in most cases the presence of Alzheimer's is diagnosed post mortem with the help of a brain tissue test.
By studying the anatomy of the brain, scientists are one step closer in finding a cure for this death ending disorder.
Showing posts with label Tau Alzheimer's. Show all posts
Showing posts with label Tau Alzheimer's. Show all posts
Monday, June 23, 2014
Alzheimer's Disease Genetics
Alzheimer's Disease Genetics
Alzheimer's disease is a common disorder affecting the central Nervous system and the brain, and has been found to be a common cause of dementia.
The basic mechanism in this disease is the formation of plaques on the brain. The amyloid cells are broken down by the enzyme beta-secretase in to smaller cells. These smaller cells then keep on accumulating and piling on each other and then finally the brain gets covered with these plaques. Theses plaques lead to the Alzheimer's disease. There are various stages of this disease, like the initial loss of intelligence. The patient loses the ability for abstract thinking, judgment, and solving of problems.
Next it progresses to Memory impairment, where events of recent happening are forgotten.
Next it progresses to the changes in personality and also in emotional outlook. All these are the late changes in the progress of the disease.
The Alzheimer's disease is not a simple process. It involves many complex factors like multiple genetic defects or mutations in the genes. These mutations can be either hereditary and passed on from generation to generation. Or it may be acquired through increased susceptibility, which in turn may be due to various other factors.
The genomics or the study of the genetic progress of the disease has revealed that the Alzheimer's disease is caused due to the aging process. The aging process either accelerates the damage of the brain cells or when the person is exposed to deleterious environmental processes. The intake of certain drugs can also cause the harmful effect.
The multiple defects in the genes are at the following mutational loci (APP, PS1, TAU, PS2) and many other different susceptibility loci (APOE, AACT, A2M, TNF, BACE, BCHE, NOS3, GSK3B)
All these loci are spread across the human genome and they all meet together to effect the deleterious changes. The combined effects of these loci lead to untimely and premature death of the neurons. The neurons are the brain cells and thus it leads to death of the brain cells. This is the mechanism of loss of function of these cells and a resultant psychiatric disease.
The damage to the neurons are in various forms like aberrations in the protein content of the mitochondria, formation of protofibrils, altered function or dysfunction of the ubiquity-proteasome system, injury to the mitochondria, piling up of folded proteins, reactions which not only excite the system but also are toxic, stress etc.
Alzheimer's disease is a common disorder affecting the central Nervous system and the brain, and has been found to be a common cause of dementia.
The basic mechanism in this disease is the formation of plaques on the brain. The amyloid cells are broken down by the enzyme beta-secretase in to smaller cells. These smaller cells then keep on accumulating and piling on each other and then finally the brain gets covered with these plaques. Theses plaques lead to the Alzheimer's disease. There are various stages of this disease, like the initial loss of intelligence. The patient loses the ability for abstract thinking, judgment, and solving of problems.
Next it progresses to Memory impairment, where events of recent happening are forgotten.
Next it progresses to the changes in personality and also in emotional outlook. All these are the late changes in the progress of the disease.
The Alzheimer's disease is not a simple process. It involves many complex factors like multiple genetic defects or mutations in the genes. These mutations can be either hereditary and passed on from generation to generation. Or it may be acquired through increased susceptibility, which in turn may be due to various other factors.
The genomics or the study of the genetic progress of the disease has revealed that the Alzheimer's disease is caused due to the aging process. The aging process either accelerates the damage of the brain cells or when the person is exposed to deleterious environmental processes. The intake of certain drugs can also cause the harmful effect.
The multiple defects in the genes are at the following mutational loci (APP, PS1, TAU, PS2) and many other different susceptibility loci (APOE, AACT, A2M, TNF, BACE, BCHE, NOS3, GSK3B)
All these loci are spread across the human genome and they all meet together to effect the deleterious changes. The combined effects of these loci lead to untimely and premature death of the neurons. The neurons are the brain cells and thus it leads to death of the brain cells. This is the mechanism of loss of function of these cells and a resultant psychiatric disease.
The damage to the neurons are in various forms like aberrations in the protein content of the mitochondria, formation of protofibrils, altered function or dysfunction of the ubiquity-proteasome system, injury to the mitochondria, piling up of folded proteins, reactions which not only excite the system but also are toxic, stress etc.
Alzheimer's Disease Gene
Alzheimer's Disease Gene
Alzheimer's disease is one that starts to affect brain cells over a significant period of time. When brain cells start sustaining this damage, the symptoms of Alzheimer's show up and these brain cells slowly start to die off. Once the dying of brain cells begins, some cognitive processes begin to fail, causing effects such as confusion, a decrease in image recognition, memory impairment and a decrease in awareness.
When a sufferer of this terrible disease reaches this stage, it is extremely difficult, and many times it is nearly impossible, to live a normal, independent life. Many who suffer with Alzheimer's need to be reminded of where they are, who they are, the dangers of every day life such as a hot kettle, the names of objects and colors, and even who their very own family members are. There are few moments during which the sufferer is aware of such things, but moments like this will continue to decrease as the disease continues. Currently, the most common cause of the disease dementia is Alzheimer's disease.
There's plenty of research taking place to find out what causes Alzheimer's disease, and how to prevent it, but there are still no clear answers when it comes to why this disease actually develops. It's quite clear that a lot more research will be needed before anyone can come close to answering this question. What is known to a great deal of certainty is the fact that once the disease begins, it progresses quite rapidly, and quick steps need to be taken to try and inhibit the rate at which this disease affects the brain, and this is done usually through medication.
Another important aspect that most researchers and experts agree on is the fact that there is nearly always a greater risk of developing Alzheimer's if there is a history of the disease in the family. This points to the fact that genes are involved in the appearance of this disease.
Many years of research have given us the conclusion that there are two genes that play a role when it comes to the development of Alzheimer's. The first gene is called the Risk Gene. Namely, this means that people who have this gene have a higher risk of getting Alzheimer's disease than those who do not have this gene. The second gene is known as the deterministic gene, and, as the name suggest, this gene is important because it guarantees whether or not someone will have to deal with Alzheimer's at some point in their life.
Alzheimer's disease is one that starts to affect brain cells over a significant period of time. When brain cells start sustaining this damage, the symptoms of Alzheimer's show up and these brain cells slowly start to die off. Once the dying of brain cells begins, some cognitive processes begin to fail, causing effects such as confusion, a decrease in image recognition, memory impairment and a decrease in awareness.
When a sufferer of this terrible disease reaches this stage, it is extremely difficult, and many times it is nearly impossible, to live a normal, independent life. Many who suffer with Alzheimer's need to be reminded of where they are, who they are, the dangers of every day life such as a hot kettle, the names of objects and colors, and even who their very own family members are. There are few moments during which the sufferer is aware of such things, but moments like this will continue to decrease as the disease continues. Currently, the most common cause of the disease dementia is Alzheimer's disease.
There's plenty of research taking place to find out what causes Alzheimer's disease, and how to prevent it, but there are still no clear answers when it comes to why this disease actually develops. It's quite clear that a lot more research will be needed before anyone can come close to answering this question. What is known to a great deal of certainty is the fact that once the disease begins, it progresses quite rapidly, and quick steps need to be taken to try and inhibit the rate at which this disease affects the brain, and this is done usually through medication.
Another important aspect that most researchers and experts agree on is the fact that there is nearly always a greater risk of developing Alzheimer's if there is a history of the disease in the family. This points to the fact that genes are involved in the appearance of this disease.
Many years of research have given us the conclusion that there are two genes that play a role when it comes to the development of Alzheimer's. The first gene is called the Risk Gene. Namely, this means that people who have this gene have a higher risk of getting Alzheimer's disease than those who do not have this gene. The second gene is known as the deterministic gene, and, as the name suggest, this gene is important because it guarantees whether or not someone will have to deal with Alzheimer's at some point in their life.
Alzheimer's Disease Brain
Alzheimer's Disease Brain
People who suffer from the Alzheimer's disease experience acute damage on brain tissues. Images of the brains of people who suffer from this disease show clear shrinkage of the brain tissue. The furrows of patient's brain change very drastically. The outer layer changes completely as well.
The chambers in the brain, scientifically known as ventricles, become enlarged. These ventricles are the ones that contain cerebrospinal fluid. This is why the short-term memory of people with the Alzheimer's disease begins to fade during the early stages of it.
The cells that are in the limbic system begin to degenerate. The patient finds it difficult to perform routine tasks. With time, the disease finds its way into the cerebral cortex. The cerebral cortex is outer part of the brain. Damage to this area is often followed by emotional outbursts and language impairment.
Continued damage to the nerve cells brings about Alzheimer's disease brain complications, which lead to continued change in the patient's behavior. A person might lose the ability to recognize even close family members. Communication becomes a problem and the patient finds it difficult to perform even the most basic of bodily functions. It can even become difficult for the patient to know when to chew and when to swallow food. If this happens, it is important for the patient to be given only soft foods that do not require a lot of chewing.
The disease typically lasts for a period of between 8 and 10 years. However, Alzheimer's disease patients can live for up to 20 years.
A good understanding of the functions of the normal brain as opposed to that of Alzheimer's disease patients can give caregivers a very clear insight into why the patient behaves in the way he does. This enables these people cope better with the circumstances that they go through.
Atrophy of the cerebral cortex best manifests itself through the dramatic way in which the brain shrinks. Since cerebral functioning is responsible for intellectual reasoning, any impairment in this area results in acute mental instability. The contents of gyri are drastically reduced at the hands of destructive proteins, which are the root causes of the Alzheimer's disease.
Neurofibrillary tangles and amyloid plaques are a common feature of the human brain. However, for people who suffer from this disease, the high number of these elements is the most significant thing that one should be looking out for.
People who suffer from the Alzheimer's disease experience acute damage on brain tissues. Images of the brains of people who suffer from this disease show clear shrinkage of the brain tissue. The furrows of patient's brain change very drastically. The outer layer changes completely as well.
The chambers in the brain, scientifically known as ventricles, become enlarged. These ventricles are the ones that contain cerebrospinal fluid. This is why the short-term memory of people with the Alzheimer's disease begins to fade during the early stages of it.
The cells that are in the limbic system begin to degenerate. The patient finds it difficult to perform routine tasks. With time, the disease finds its way into the cerebral cortex. The cerebral cortex is outer part of the brain. Damage to this area is often followed by emotional outbursts and language impairment.
Continued damage to the nerve cells brings about Alzheimer's disease brain complications, which lead to continued change in the patient's behavior. A person might lose the ability to recognize even close family members. Communication becomes a problem and the patient finds it difficult to perform even the most basic of bodily functions. It can even become difficult for the patient to know when to chew and when to swallow food. If this happens, it is important for the patient to be given only soft foods that do not require a lot of chewing.
The disease typically lasts for a period of between 8 and 10 years. However, Alzheimer's disease patients can live for up to 20 years.
A good understanding of the functions of the normal brain as opposed to that of Alzheimer's disease patients can give caregivers a very clear insight into why the patient behaves in the way he does. This enables these people cope better with the circumstances that they go through.
Atrophy of the cerebral cortex best manifests itself through the dramatic way in which the brain shrinks. Since cerebral functioning is responsible for intellectual reasoning, any impairment in this area results in acute mental instability. The contents of gyri are drastically reduced at the hands of destructive proteins, which are the root causes of the Alzheimer's disease.
Neurofibrillary tangles and amyloid plaques are a common feature of the human brain. However, for people who suffer from this disease, the high number of these elements is the most significant thing that one should be looking out for.
Alzheimer's Disease Amyloid
Alzheimer's Disease Amyloid
'Alzheimer's Disease' (AD) is characterized by affected parts of the brain that control memory, thought and language. It is a slowly progressive disease which develops in the brain by attacking the patient's abilities of planning, reasoning, perception, and language. The cause of Alzheimer's disease is unknown, yet scientists believe that accumulated beta-amyloid protein is the main cause behind this brain disease, which leads death of nerve cells. It is a type of dementia that occurs when the patient crosses his 60s. It is noted that certain chemical reaction brings out shrinkage of the brain, which leads to cluttering of the entwined cells. In 1906, Alois Alzheimer, a German neuropathologist and psychiatrist, first discovered this incurable disease. Hence, this terminal and degenerative disease was named after this German scientist. It is reported that until now more than 35 million people throughout the world are suffering from Alzheimer's disease. A reputed survey claims that by 2050 this number will increase up to 107 million.
As described earlier the Alzheimer's disease occurs after the age of 60. Difficulty in performing even the daily tasks, loss of memory, disorientation to time and place, language problems, decreased or poor judgment, changes in mood or behavior, misplacing things, changes in personality, problems with abstract thinking, and loss of initiative are some of the warning signs of this brain disease. The patient's simple forgetfulness is acutely noticeable. His normal activities like hygiene, dressing, or going to the marketplace are disturbed. Gradually, the person depends on others to execute even the regular simple tasks like an infant. Sadly enough, there is no cure for Alzheimer's, but the available treatments are sufficed to alleviate some of the symptoms and thus this can reduce the patient's sufferings.
The diagnostic tools like SPECT and PET scans confirm the AD that display temporal lobe's inability to function actively. The patient's history, clinical observations, and collateral history from relatives are helpful to diagnose this disease. Memory testing with intellectual functioning assessment shows the state of the disease. Cerebrospinal fluid analysis for tau proteins or amyloid beta is another criterion to diagnose the disease. The epidemiological study has put forth relationship between some modifiable things like diet, intellectual activities in others, or pharmaceutical products, cardiovascular risk, and a population's possibility of developing AD. However, the further ongoing research along with the clinical trials will determine whether these things can assist in preventing the AD.
'Alzheimer's Disease' (AD) is characterized by affected parts of the brain that control memory, thought and language. It is a slowly progressive disease which develops in the brain by attacking the patient's abilities of planning, reasoning, perception, and language. The cause of Alzheimer's disease is unknown, yet scientists believe that accumulated beta-amyloid protein is the main cause behind this brain disease, which leads death of nerve cells. It is a type of dementia that occurs when the patient crosses his 60s. It is noted that certain chemical reaction brings out shrinkage of the brain, which leads to cluttering of the entwined cells. In 1906, Alois Alzheimer, a German neuropathologist and psychiatrist, first discovered this incurable disease. Hence, this terminal and degenerative disease was named after this German scientist. It is reported that until now more than 35 million people throughout the world are suffering from Alzheimer's disease. A reputed survey claims that by 2050 this number will increase up to 107 million.
As described earlier the Alzheimer's disease occurs after the age of 60. Difficulty in performing even the daily tasks, loss of memory, disorientation to time and place, language problems, decreased or poor judgment, changes in mood or behavior, misplacing things, changes in personality, problems with abstract thinking, and loss of initiative are some of the warning signs of this brain disease. The patient's simple forgetfulness is acutely noticeable. His normal activities like hygiene, dressing, or going to the marketplace are disturbed. Gradually, the person depends on others to execute even the regular simple tasks like an infant. Sadly enough, there is no cure for Alzheimer's, but the available treatments are sufficed to alleviate some of the symptoms and thus this can reduce the patient's sufferings.
The diagnostic tools like SPECT and PET scans confirm the AD that display temporal lobe's inability to function actively. The patient's history, clinical observations, and collateral history from relatives are helpful to diagnose this disease. Memory testing with intellectual functioning assessment shows the state of the disease. Cerebrospinal fluid analysis for tau proteins or amyloid beta is another criterion to diagnose the disease. The epidemiological study has put forth relationship between some modifiable things like diet, intellectual activities in others, or pharmaceutical products, cardiovascular risk, and a population's possibility of developing AD. However, the further ongoing research along with the clinical trials will determine whether these things can assist in preventing the AD.
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